Refrigerated freight container

ABSTRACT

A refrigerated freight container is provided comprising thermally insulated sidewalls [ 2],  roof [ 3]  and floor [ 4],  a thermally insulated access opening at one end of the container and a refrigeration installation [ 10]  at the other end of the container. The refrigeration installation is built into a removable end wall unit [ 8]  that closes off the end of the container opposite the access opening in the installed position. The access opening preferably includes a surrounding frame [ 7]  forming an access opening unit that is also removable from the container. The sidewalls of the container are preferably hinged [ 15]  in a central region up the height thereof so that they can collapse inwardly in concertina fashion with the roof moving towards the floor of the container and the central regions of the sidewalls folding inwardly towards each other. A separate holder [ 20]  may be provided for holding one or more removable end wall units and one or more removable access opening units [ 5]  when the container is in the collapsed condition.

FIELD OF THE INVENTION

This invention relates to refrigerated freight containers for theshipping and/or storage of perishable goods that may be simplyrefrigerated to temperatures somewhat above 0° C. or that may be frozen.The invention is applicable to maritime transport containers, air-cargocontainers, as well as rail- and road transport containers.

BACKGROUND TO THE INVENTION

As a result of the fact that the world-wide flow of cargo is not inbalance in terms of import and export from any particular harbour,especially as regards fresh produce being transported from a producercountry to a consumer country, a large number of empty freightcontainers has to be returned empty to the producer country for re-use.It is even quite common to charter container vessels merely to transportempty freight containers back to where they are required.

Furthermore, since empty containers occupy the same volume as loadedcontainers, their storage, too, is increasingly expensive with thegrowing use of containers for shipping. A solution that has beenproposed is to produce collapsible containers that can be returned tothe place where they are required for use in a collapsed condition andtherefore of very much reduced size.

United States patents U.S. Pat. No. 5,19,0179 and U.S. Pat. No.4,214,669 and Canadian patent CA2636126 describe one mode of collapsingconventional containers [as opposed to refrigerated containers thatnormally include refrigeration equipment built into them] is for the endwalls of the container to hinge inwards against either the floor orceiling of the container with the sidewalls being hinged in the centralregion up their height to collapse inwardly in concertina fashion.Applicant is not aware of any practical implementation of thisarrangement.

The most important requirement of any collapsible container is that itshould be capable of being stacked with other collapsible ornon-collapsible containers.

Applicant is unaware of any prior attempts to produce a collapsiblerefrigerated container having refrigeration equipment built into it.

OBJECT OF THE INVENTION

It is an object of this invention to provide a refrigerated freightcontainer that has at least some of the advantages of a collapsibleconventional non-refrigerated freight container.

SUMMARY OF THE INVENTION

In accordance with this invention there is provided a refrigeratedfreight container comprising thermally insulated sidewalls, roof andfloor, a thermally insulated access opening at one end of the containerand a refrigeration installation at the other end of the container, therefrigerated container being characterized in that the refrigerationinstallation is built into a removable end wall unit that closes off theend of the container opposite the access opening in the installedposition.

Further features of the invention provide for the access opening toinclude a surrounding frame forming an access opening unit that isremovable from the container; for the sidewalls of the container to behinged in a central region up the height thereof so that they cancollapse inwardly in concertina fashion with the roof moving towards thefloor of the container and the central regions of the sidewalls foldinginwardly towards each other; for the sides of the roof and floor or bothto have formations that may interconnect when the freight container isin the collapsed condition to maintain the roof and floor in thecollapsed condition; and for a separate holder to be provided forholding the removable end wall unit and the removable access openingunit when the container is in the collapsed condition with a singleholder preferably being configured to receive the removable end wallunits and access opening units from multiple collapsed freightcontainers.

In order that the invention may be more fully understood one embodimentthereof will now be described with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:—

FIG. 1 is a schematic isometric view of a refrigerated shippingcontainer with a removable end wall unit in exploded relationshiprelative to the container body;

FIG. 2 is a schematic side view of the container showing both theremovable end wall unit and removable access opening unit in explodedrelationship relative thereto;

FIG. 3 is a schematic isometric view illustrating a holder for holdingmultiple removable end wall units and access opening units when theircontainers are in the collapsed condition;

FIG. 4 is a schematic isometric view illustrating multiple collapsedcontainers in stacked relationship relative to each other; and,

FIGS. 5 a, 5 b, and 5 c are schematic end views illustrating thecontainer body in its erected, partially collapsed, and fully collapsedconditions respectively.

DETAILED DESCRIPTION WITH THE REFERENCE TO THE DRAWINGS

In one embodiment of the invention a refrigerated freight container hasa body, generally indicated by numeral [1], comprising thermallyinsulated sidewalls [2], a roof [3] and a floor [4].

At one end of the freight container is a modular, thermally insulatedaccess opening unit [5] in the form of a pair of thermally insulateddoors [6] mounted in a surrounding frame [7]. The access opening unit[5] is thus removable relative to one end of the container.

At the opposite end of the freight container is a modular, removable endwall unit [8] that, as provided by this invention, has a refrigerationinstallation built into it. This removable end wall unit [8] operativelycloses off the end of the container opposite the access opening unit inthe installed position. The refrigeration installation may comprise anappropriate prime mover that is indicated by numeral [9] and that may bein the form of an engine or an electric motor, depending upon the vesselin association with which the refrigerated freight container is to beused. In this regard, appropriate reefer ships generally have a suitableelectrical power supply for each of the containers carried by it. Thenature of the prime mover may also depend on whether or not therefrigerated container is to be used above or below deck, this beingparticularly relevant if the prime mover is an internal combustionengine.

The prime mover is adapted to energize a refrigeration unit that isindicated schematically by numeral [10] and that is adapted torefrigerate air for circulation through the container in the usual waythrough channels and ducts [not shown] of the usual or any other type.The removable end wall unit has a service and venting opening [11] forproviding access to the refrigeration unit as and when required.

The access opening unit [5] and removable end wall unit [8] are capableof being inserted into the container body after its erection, and ofremoved from it before collapsing it. Both the access opening unit [5]and removable end wall unit [8] are fitted with suitable internallyaccessible sliding locks to lock the units into their operativepositions after insertion. The peripheries of the access opening unit[5] and removable end wall unit [8] are fitted with suitable elastomericseals.

Turning now to the construction of the container body, each of thesidewalls [2] is hinged in a central region up the height thereof, asindicated by numeral [15], so that they can collapse inwardly inconcertina fashion with the roof [3] moving towards the floor [4] of thecontainer. The central regions of the sidewalls thus fold inwardlytowards each other during the collapsing process.

In a preferred arrangement the sides of the roof [3] and floor [4] haveformations [16, 17] [see FIG. 5 b] that can be used to interconnect theroof and floor when the freight container is in the collapsed conditionto maintain the container body in that collapsed condition.

Internal sliding bolt locks [18] [see FIG. 5 a] are provided to keep theside-walls [2] from folding inwards during removal and introduction ofthe access opening unit and removable end wall unit during the erectionor collapsing procedure.

In order to weather-proof the container, all mating surfaces of foldingor opening panels maybe fitted with rubber strip seals and/or rubberaprons. The open end of the collapsed container, therefore, is coveredby such rubber seals, as is the longitudinal side opening at the upperand lower mating surfaces of the side-walls.

It will be understood that in order to facilitate the handling andstacking of the collapsible containers alongside conventionalcontainers, both the floor and roof of the container body conform tostandard dimensions and features, as used in the industry, and employstandard format corner blocks that cooperate with corner blocks on othercontainers that may be stacked upon them or upon which they may bestacked.

Referring now to FIG. 3, a separate holder [20] is preferably providedfor holding multiple removable wall units and removable access openingunits when a plurality of freight containers are in the collapsedcondition for transport and storage purposes. The holder may be akin toa pallet or flat rack that is configured to store and transport theremovable units when they are separated from their collapsible containerbodies. The holder is preferably fitted with protective side-walls [21]and the removable units may be loaded and unloaded from the holder bymeans of a mobile lifting device that can be used to transport the unitsto the erected container body for installation. The holder can, in thealternative, be a closed container that may even be a standard andoptionally a collapsible container.

FIGS. 5 a through 5 c show the progressive folding of the container bodyfrom its fully erected form to its fully collapsed form.

In order to collapse a container of the type described above from thefully erected condition, the access opening unit [5] and removable endwall unit [8] are firstly released and removed, as illustrated in FIG.2. The removed insulated access opening units [5] and removable end wallunits [8] can be introduced into the separate holder as will be apparentfrom the foregoing. A suitable mobile crane can be used for thispurpose.

The mobile crane can then be attached to the roof and placed under aslight lifting action so that the container side-walls can then beunlocked by releasing the sliding bolt locks and allowing the sidewallsto collapse inwards as the roof is lowered towards the floor. The resultis that the sidewalls become folded within the original foot-print ofthe container that occupies, in the collapsed condition, only about20-25% of its original volume, depending on the type of container andthe insulation in the sidewalls, roof and floor.

The container roof may then be locked to the container floor by means ofthe formations [16, 17], enabling the collapsed unit to be handled likeany normal container. The entire collapsing or re-erection procedure canbe performed by one man within a few minutes using a small mobile crane.

Once this has been achieved, the collapsed freight containers can bestacked one upon the other and suitable fastener clips [19] may be usedto connect the collapsed units to each other to thereby allow an entirestack to be handled as a single unit. FIG. 4 illustrates a stack of fourcollapsed container bodies.

It will be understood, that the embodiment of the invention describedabove is a conceptual design of quite a complex assembly. As such,numerous variations may be made to structural, mechanical and materialdesign details, without departing from the scope of the invention. Thebasic principle of the invention; the removable end wall unit containingthe refrigeration installation built into it, coupled with thecollapsible container being the main concept of the invention. Theremovable access opening unit is also of importance as it enables thecollapsing of the container to be carried out most compactly.

The manner of collapsing of the container is not essential but it ispreferred that the sidewalls fold inwards in concertina fashion asdescribed above. The principles of the invention can apply equally wellto a wide range of refrigerated freight containers, from standardrefrigerated maritime shipping containers to wheeled refrigeratedairfreight containers. Clearly, the peripheral design details of thiswide range of containers will result in an equally wide range of designswhile still incorporating the basic invention, as described above.

1. A refrigerated freight container comprising thermally insulatedsidewalls, roof and floor, a thermally insulated access opening at oneend of the container and a refrigeration installation at the other endof the container, wherein the refrigeration installation is built into aremovable end wall unit that closes off the end of the containeropposite the access opening in the installed position; wherein thesidewalls of the container are hinged in a central region up the heightthereof so that they can collapse inwardly in concertina fashion withthe roof moving towards the floor of the container and the centralregions of the sidewalls folding inwardly towards each other.
 2. Arefrigerated freight container as claimed in claim 1 in which the accessopening includes a surrounding frame forming an access opening unit thatis removable from the container.
 3. (canceled)
 4. A refrigerated freightcontainer as claimed in claim 1 in which for the sides of the roof andfloor or both have formations that interconnect when the freightcontainer is in the collapsed condition to maintain the roof and floorin the collapsed condition.
 5. A refrigerated freight container asclaimed in claim 1 in which a separate holder is provided for holding aremovable end wall unit and a removable access opening unit when thecontainer is in the collapsed condition.
 6. A refrigerated freightcontainer as claimed in claim 5 in which the separate holder isconfigured to receive the removable end wall units and access openingunits from multiple collapsed freight containers.